Integrating combined cooling heating and power systems with biomass gasification is a sustainable means of simultaneously using renewable energy and improve energy utilization efficiency. A combined cooling heating and power system based on biomass gasification is integrated with a heat exchanger to recover waste heat from the high-temperature product gas for effective utilization in different operating conditions. The exergy efficiencies and the exergy destructions in the cooling and heating modes are calculated. Next, the unit exergy-based cost of products is calculated, and the cost allocation is discussed using the specific exergy costing approach, including electricity, water for cooling or heating, and domestic hot water. A sensitivity analysis is presented to obtain the unit exergy cost of the products along with the influence factors, such as biomass cost, investment capital, interest rate, service life and operating time. Finally, the selling price coefficient of the product cost is obtained to recover the installation cost. The results indicate that the exergy cost ratio of the three products is 1.0:7.5:3.5 (electricity, chilled water and domestic hot water, respectively) in the cooling mode and 1.0:6.0:3.5 (electricity, hot water for heating and domestic hot water, respectively) in the heating mode for the base design. (C) 2015 Elsevier Ltd. All rights reserved.